What Do You Do If You’re Trapped in a Mine?

First, try your self-contained self-rescuer.

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Living life like a canary in a coal mine

Thirteen miners were trapped underground after an explosion at a West Virginia mine on Monday. A rescue team punched a hole into the mine the next morning and discovered dangerous levels of carbon monoxide. An official from the company that owns the mine said workers are trained to build barricades around an area with breathable air and then wait for a rescue team. Is that really a good idea?

Only as a last resort. As soon as a miner discovers a problem, he should reach for his self-contained self-rescuer, a breathing apparatus designed to provide oxygen for at least one hour. An SCSR weighs about 7 pounds and comprises a mouth tube, nose clips, a pair of goggles, and an oxygen box worn in front of the chest. Some are small enough to be worn on a miner’s belt; others are kept in side passages off the mine’s main tunnel. Anyone who doesn’t carry an SCSR should have a smaller device, called a W-65, that can filter out carbon monoxide—at least for a while.

Each new underground miner learns how to put on an SCSR during the 40-hour training course required by federal law. (Some states extend the training; in West Virginia, you’ll spend 80 hours in class before you can start work.) The course syllabus includes fires, roof collapses, and other emergencies.

In most cases, a miner would put on his SCSR and then make for the nearest safe escape route. His best bet would be an intake passage, which links to the outside and provides fresh air to the mine. Intake routes are marked all the way to the exit with color-coded reflectors. (They’re often green; a secondary escape route might be marked in red.) If there’s no power or light, a miner might be able to use a rope attached to the wall or ceiling as a guide.

If the escape route is blocked off, and there’s absolutely no way to get to another one, miners are trained to barricade themselves into a relatively safe place. First, they use hand-held gas monitors to find a spot with clean air—an intake passage might be pretty good, even if it’s blocked off on one end. (Not every miner carries a gas monitor: Every foreman should have one, as should any miner who operates heavy equipment.)

The barricade can be made of anything as long as it’s airtight. Miners might use rubble, cement blocks, pieces of equipment, or the brattice cloth normally used to deflect air and promote ventilation. Tools or special materials for building barricades might be kept in emergency-supply stores throughout the mine.

Bonus Explainer: Do miners still use canaries to detect poisonous gas? No, but the birds haven’t been obsolete for very long. British miners used them throughout the 20th century. Because canaries have fast-beating hearts and a quick metabolism, even a small amount of carbon monoxide will make them totter and fall. (A canary that stops singing also sounds an alarm.) In modern times, birds were kept in a plastic case with ventilation holes; miners could save and reuse them by sealing up the case at the first signs of poisoning. The last coal-mine canaries in the United Kingdom were retired in 1996. (Some people have looked to canaries for advance warning of a terrorist attack; at the end of 2001, New York City pet-store owners told newspapers they were selling the birds in record numbers.)